Is it true that vitamin D can increase the risk of prostate cancer in men?

Answer:

It is true that a recently published study concluded "that men with higher vitamin D blood levels are at increased risk of developing prostate cancer." HOWEVER, a closer look at the data in this study showed that it only applied to men with very high calcium intake. Most other studies have not found this link. For more details, see the update to the Vitamin D Supplements Review.